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For alloys containing transition metal elements there is a difficulty in interpretation of the Hume-Rothery electron concentration rule, as the values of e/a values (number of itinerant electrons per atom) for transition metals have been quite controversial for a long time, and no satisfactory solutions have yet emerged. [9] [10]
Electrochemical stripping analysis is a set of analytical chemistry methods based on voltammetry [1] or potentiometry [2] that are used for quantitative determination of ions in solution. [3] Stripping voltammetry (anodic, cathodic and adsorptive) have been employed for analysis of organic molecules as well as metal ions.
The general expression Qualitative Analysis [...] refers to analyses in which substances are identified or classified on the basis of their chemical or physical properties, such as chemical reactivity, solubility, molecular weight, melting point, radioactivity properties (emission, absorption), mass spectra, nuclear half-life, etc. Quantitative Analysis refers to analyses in which the amount ...
Complexometric titrations are particularly useful for the determination of a mixture of different metal ions in solution. An indicator capable of producing an unambiguous color change is usually used to detect the end-point of the titration. Complexometric titrations are those reactions where a simple ion is transformed into a complex ion and ...
More sophisticated approaches are used in the determination of trace metals and organic compounds. Metals are commonly measured by atomic spectroscopy and mass spectrometry : Atomic Absorption Spectrophotometry (AAS) and Inductively Coupled Plasma Atomic Emission (ICP-AES) or Inductively Coupled Plasma Mass Spectrometric (ICP-MS) techniques.
Gravimetric analysis describes a set of methods used in analytical chemistry for the quantitative determination of an analyte (the ion being analyzed) based on its mass. The principle of this type of analysis is that once an ion's mass has been determined as a unique compound, that known measurement can then be used to determine the same analyte's mass in a mixture, as long as the relative ...
At the time, elemental analysis was based on the gravimetric determination of specific absorbent materials before and after selective adsorption of the combustion gases. [ 1 ] [ 2 ] Today fully automated systems based on thermal conductivity or infrared spectroscopy detection of the combustion gases, or other spectroscopic methods are used.
Metallurgy derives from the Ancient Greek μεταλλουργός, metallourgós, "worker in metal", from μέταλλον, métallon, "mine, metal" + ἔργον, érgon, "work" The word was originally an alchemist's term for the extraction of metals from minerals, the ending -urgy signifying a process, especially manufacturing: it was discussed in this sense in the 1797 Encyclopædia ...